Otter, Affordable Newborn warmer

video made by Malory Johnson

International research, design and prototype of a newborn warmer that will prevent hypothermia in developing countries

Company: Design that Matters

Project Outcome: Multiple iterations on the Otter warmer including the latest alpha-prototype, currently being used to refine manufacturing details to bring the concept to market in 2019.  
2015 - present

Team: Lead: Malory Johnson
ID: Karan Mudgal
ME: Kristine Chen
ME: Kelly Brennan
ME: Celine Ta
Clinical research: Kristen Moulton

Project website


Interview with Dr. Ryan Carroll, global health expert who works as a doctor in Uganda.

Interview with Dr. Ryan Carroll, global health expert who works as a doctor in Uganda.

Video (right) follows our most recent field research story and explains our approach to human factors and design research.

"as designers we want to solve the problems that exist, but acknowledge and preserve what already works"

Made by Malory Johnson


Prototyping Process


objective: Universally Intuitive UI

For Otter's design to reflect the philosophy of Design that Matters, it must be "hard to use wrong." That means the interface must transcend language and culture to be intuitive to hospital staff from South-East Asia to Sub-Saharan Africa. 

I've led two internal projects to build a functional prototype intended to be an international research tool. Each model both looks and works like the current (at the time) Otter design.




First concepts
(before my involvement)
Heater: phase-changing wax
Bassinet: double walled
UI: good/bad light indicators

OTTER Model 3.jpg

2016 prototype
Heater: nichrome wires/air pocket
Bassinet: double walled
UI: progress/ready lights

2017 Summer UI prototype.jpg

2017 prototype
Heater: polymer adhesive film
Bassinet: single walled (cheaper!)
UI: familiar icon-based UI


Fabrication Process

We've used a variety of low-volume manufacturing equipment along with hand finishing techniques to create these prototypes. CNC milled, 3D printed and Laser Cut parts are all finished with sandpaper, Bondo and occationally, the shameful hot glue gun. 


Each prototype starts in CAD

These models were made in Fusion 360 and Inventor. We use one master file to export STLs and GCODE.  

Modeling (fusion).JPG

Print and test the fit

We 3D print many housing iterations with minor adjustments to account for variation in the printing process. We use a vacuum-former to create the bassinet body.


Finish 3D printed parts

Sand, fill, prime, rinse and repeat. We work to simulate the look of plastic injection molded parts.



Pack the electronics

Lastly, we fill the finished housings with the electronics and pray everything still works. Electrical engineering was accomplished by Kristine Chen, Kelly Brennan and Celine Ta


Ready for International testing!


Thanks to my wonderful team! 

Thanks to my wonderful team!